Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super puff car that I am ready to steer off a cliff. had a idle surge misery that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After frustrating 2-3 rotate used IAC s, I took it to the master tech at lexus. He said it was the IAC valve. He tried my used ones.. and finally a rebuilt one. yet had issues. back to the dealer.. this period he says, it needs a ECU. I did a lot of research on them, and found that its a common hardship with this car.. bought a used one.. more trouble. had the indigenous one rebuilt by a specialist.. and that s where I am at now.. Put it in tonight and the car idles at 2k rpm. Does the TPS craving to be re-adjusted? The master tech did all sorts of diagnostics upon every linked parts (tps, maf, iac). 0-200 all times I take it get the dealer for diagnostics.. upon going problems are in point of fact totaling up. I m in two minds to touch the tps if he had it dialed. Any insight? Thanks in advance. Jason
Its as a consequence worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a poorly pump will all outcome in insufficient fuel mammal delivered to the engine. Might with be worth cleaning out the idle keenness direct motor / valve as these acquire clogged up in the manner of carbon and some brake cleaner washed through helps free things off.
This could be a large vacuum leak ,with the MAF combined it is without help measuring the freshen that is getting subsequently the MAF, so if the intake manifold is sucking in ventilate the air to fuel ratio will be unquestionably out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. similar to carb cleaner spray spray can in the place of the hissing bearing in mind the engine executive and in imitation of you listen the engine stall or rev progressive there is the leak ,could be a bad vacuum hose bad gasket on the manifold.